CVE-2020-1683

Junos OS: Memory leak leads to kernel crash (vmcore) due to SNMP polling

Description

On Juniper Networks Junos OS devices, a specific SNMP OID poll causes a memory leak which over time leads to a kernel crash (vmcore). Prior to the kernel crash other processes might be impacted, such as failure to establish SSH connection to the device. The administrator can monitor the output of the following command to check if there is memory leak caused by this issue: user@device> show system virtual-memory | match "pfe_ipc|kmem" pfe_ipc 147 5K - 164352 16,32,64,8192 <-- increasing vm.kmem_map_free: 127246336 <-- decreasing pfe_ipc 0 0K - 18598 32,8192 vm.kmem_map_free: 134582272 This issue affects Juniper Networks Junos OS: 17.4R3; 18.1 version 18.1R3-S5 and later versions prior to 18.1R3-S10; 18.2 version 18.2R3 and later versions prior to 18.2R3-S3; 18.2X75 version 18.2X75-D420, 18.2X75-D50 and later versions prior to 18.2X75-D430, 18.2X75-D53, 18.2X75-D60; 18.3 version 18.3R3 and later versions prior to 18.3R3-S2; 18.4 version 18.4R1-S4, 18.4R2 and later versions prior to 18.4R2-S5, 18.4R3-S1; 19.1 version 19.1R2 and later versions prior to 19.1R2-S2, 19.1R3; 19.2 version 19.2R1 and later versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S5, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS prior to 17.4R3.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 17.4R3-S1, 18.1R3-S10, 18.2R3-S3, 18.2X75-D41, 18.2X75-D430, 18.2X75-D53, 18.2X75-D60, 18.3R3-S2, 18.4R2-S5, 18.4R3-S1, 19.1R2-S2, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S5, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1, and all subsequent releases.

Workaround:

  • Disable SNMP (disabled by default), utilize edge filtering with source-address validation (uRPF, etc.), access control lists (ACLs), and/or SNMPv3 authentication to limit access to the device only from trusted hosts.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.37%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11080 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1683?
CVE-2020-1683 has been scored as a high severity vulnerability.
How to fix CVE-2020-1683?
To fix CVE-2020-1683: The following software releases have been updated to resolve this specific issue: Junos OS 17.4R3-S1, 18.1R3-S10, 18.2R3-S3, 18.2X75-D41, 18.2X75-D430, 18.2X75-D53, 18.2X75-D60, 18.3R3-S2, 18.4R2-S5, 18.4R3-S1, 19.1R2-S2, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S5, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1, and all subsequent releases.
Is CVE-2020-1683 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1683 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-1683?
CVE-2020-1683 affects Juniper Networks Junos OS.
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